The key to quickly covering an entire country using real world data was a spreadsheet I created.
As you can see there is an input section at the top left. All I need to do is cut and paste the info from the Aeronautical Information Publication for the UK (available at http://www.nats-uk.ead-it.com/public/index.php.html)
If I include a comms frequency it will automatically include that as well.
All I need to do is press a key and the spreadsheet will output the correctly formatted xml code for use in flight sim for that airspace. All that needs to be done is to cut and paste that into a txt document and drop it onto bglcomp.exe from the SDK.
Hey presto! There is then a nice bgl to use in your preferred simulator....
Obviously all the magic happens on a sheet behind this one!!!!